Green Synthesis of Waste-Derived Metal–Organic Frameworks for Organic Substance Extraction from Piggery Wastewater as Biofertilizers

Management of piggery wastewater and plastic waste poses significant challenges to global environmental sustainability. This study presents an integrated approach to address these challenges by valorizing poly(ethylene terephthalate) (PET) waste and also tackling piggery wastewater issues through a sustainable supply chain. The performance of a gentle hydrolysis-microwave process was evaluated for creating MIL-53(Al) metal-organic frameworks from waste PET following green chemistry principles. MIL-53(Al) was utilized as an adsorbent to recover organic substances from piggery wastewater, and key design parameters of the recovery process were determined from kinetics, isotherm, and thermodynamics perspectives. Cost analysis, green chemistry metrics, and life-cycle environmental assessment were also conducted, demonstrating the environmental feasibility and economic viability of the integrated approach. The results reveal the PET-to-fertilizer supply chain as a pivotal green technology within the biocircular-green economy among municipal, agriculture, and livestock sectors.